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Analysis of the Factors That Cause Environmental Degradation of Lake Santa Maria Tasi Tolu Dili Timor-Leste
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作者 Antero Freitas Branco 《Journal of Geoscience and Environment Protection》 2024年第10期55-67,共13页
This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the... This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the lake as a place to live, the absence of maximum control from the local government this case, the Dili municipal authority. Types of solid waste consist of iron from car accidents, motorcycles, used building materials, plastic, used drink bottles and clothes, mosquito nets, food scraps from household waste, as well as old fishing nets from residents. In addition, household waste such as bath and bath, dishwashing, detergents, and waste from tempeh and tofu factories, including burnt oil from cars and motorcycles, are thrown into the lake. Municipal waste management is based on environmental standards to determine the quality of waste management in Dili Municipality. It is possible to identify the composition of waste and waste, as well as predict its environmental impact. Human (Anthropic) factors Domestic Liquid Waste, Domestic Solid Waste: Composed of organic and inorganic waste. Synthetic Waste, Disposal of Used Oil, Disposal of Domestic Animal Waste, Shallow Drains and Septic Tanks, Mountain Garbage, Garbage Thrown by Visitors, Natural Factors, Climate change, Prolonged drought, Low rainfall, El Niño and La Niña factors, Wind speed, Heat (high daily temperature pressure), Greater water evaporation, Dry wind. The occurrence of contamination necessarily implies an ecological imbalance. The impact introduced by residual compounds and waste that may be associated with the toxicity. 展开更多
关键词 ANALYSIS The Factors CAUSE DEGRADATION environment Santa Maria lake Tasi Tolu
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A climatic environmental performance assessment method for ecological city construction:Application to Beijing Yanqi Lake 被引量:1
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作者 FANG Xiao-Yi CHENG Chen +3 位作者 LIU Yong-Hong DU Wu-Peng XIAO Xiao-Jun DANG Bing 《Advances in Climate Change Research》 SCIE CSCD 2015年第1期23-35,共13页
In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches... In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources. 展开更多
关键词 Ecological city construction Ventilation environment Thermal environment Performance assessment Yanqi lake ecological development demonstration area
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Determining the groundwater basin and surface watershed boundary of Dalinuoer Lake in the middle of Inner Mongolian Plateau,China and its impacts on the ecological environment 被引量:2
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作者 Wen-peng Li Long-feng Wang +3 位作者 Yi-long Zhang Li-jie Wu Long-mei Zeng Zhong-sheng Tuo 《China Geology》 2021年第3期498-508,共11页
The surface watershed and groundwater basin have fixed recharge scale,which are not only the basic unit for hydrologic cycle research but also control the water resources formation and evolution and its corresponding ... The surface watershed and groundwater basin have fixed recharge scale,which are not only the basic unit for hydrologic cycle research but also control the water resources formation and evolution and its corresponding eco-geological environment pattern.To accurately identify the boundary of the surface watershed and groundwater basin is the basis for properly understanding hydrologic cycle and conducting the water balance analysis at watershed scale in complicated geologic structure area,especially when the boundary are inconsistent.In this study,the Dalinuoer Lake located in the middle of the Inner Mongolian Plateau which has complicated geologic structure was selected as the representative case.Based on the multidisciplinary comprehensive analysis of topography,tectonics,hydrogeology,groundwater dynamics and stable isotopes,the results suggest the following:(1)The surface watershed ridge and groundwater basin divide of Dalinuoer Lake are inconsistent.The surface watershed was divided into two separate groundwater systems almost having no groundwater exchange by the SW-NE Haoluku Anticlinorium Fault which has obvious water-blocking effect.The surface drainage area of Dalinuoer Lake is 6139 km^(2).The northern regional A is the Dalinuoer Lake groundwater system with an area of 4838 km^(2),and the southern regional B is the Xilamulun Riverhead groundwater system with an area of 1301 km^(2).(2)The groundwater in the southern of regional A and the spring-feeding river are the important recharge sources for the Dalinuoer Lake,and it has greater recharge effects than the northern Gonggeer River system.(3)It is speculated that the trend of Haoluku Anticlinorium Fault is the boundary of the westerlies and the East Asian summer Monsoon(EASM)climate systems,which further pinpoints the predecessor’s understanding of this boundary line.At present,the Dalinuoer Lake watershed is proved to have gone through a prominent warming-drying trend periods,which leads to the precipitation reduction,temperature rise,human activities water usage increasement.So the hydrological cycle and lake eco-environment at watershed scale will still bound to be change,which may pose the potential deterioration risk on the suitability of fish habitat.The results can provide basic support for better understanding water balance evolution and lake area shrinkage cause as well as the ecological protection and restoration implementation of Dalinuoer Lake watershed. 展开更多
关键词 Groundwater basin Surface watershed Ecological environment Hydrogeology condition Stable environmental isotopes Geologic stucture Dalinuoer lake Mongolian Plateau
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The climatic and hydrological changes and environmental responses recorded in lake sediments of Xinjiang,China 被引量:6
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作者 Long MA JingLu WU Jilili Abuduwaili 《Journal of Arid Land》 SCIE 2011年第1期1-8,共8页
Based on the analyses of environmental proxy data in lake sediments and instrumental records of Xinjiang in northwest China, the Holocene climate and hydrological variability and its environmental responses were studi... Based on the analyses of environmental proxy data in lake sediments and instrumental records of Xinjiang in northwest China, the Holocene climate and hydrological variability and its environmental responses were studied in different time scales and regions. The results showed that the Holocene climate variability had obvious differences between the north and south of Xinjiang. In northern Xinjiang, the Holocene climate was dry in the early period, humid in the middle period, and then changed to dry in the late period. However, the climate transition times were not consistent in different regions. In southern Xin- jiang, although there were many different types of climate change patterns inferred from different catch- ments, the warm and wet climate was recorded in most lake sediments in the middle Holocene. According to comparisons of some millennium scale records in lake sediments, the climate was warm and dry in the past 100 years. It can be concluded the climate showed a trend of aridity in Holocene. Especially in recent 50 years, the lake area has been shrinking rapidly because of the population growth and social economic development, which brings some environmental problems. Lake level and area changes were sensitively affected by the climate variation in geological history of Xinjiang and the lake level will continue to shrink because of the drought climate and strengthened human activities. 展开更多
关键词 HOLOCENE climate variation lake level lake sediment arid environment
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Development and Utilization of Saline Lake Resources and Protection of Ecological Environment in Qaidam Basin in Qinghai Province 被引量:3
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作者 MENG Wei SHU Jianmin +1 位作者 YANG Rongjin LI Yanwu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期191-193,共3页
Qaidam basin is an important part of National Key Development Area–Lanzhou-Xining Area,is a key region of resource development in Western Development,is a National Circular Economy Pilot Zone.The focus of
关键词 saline lake resources development and utilization protection of ecological environment Qaidam Basin.
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Improvement of Glacial Lakes Detection under Shadow Environment Using ASTER Data in Himalayas, Nepal 被引量:2
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作者 CHEN Wenbo FUKUI Hiromichi +1 位作者 DOKO Tomoko GU Xingfa 《Chinese Geographical Science》 SCIE CSCD 2013年第2期216-226,共11页
The detection of glacial lake change in the Himalayas, Nepal is extremely significant since the glacial lake change is one of the crucial indicators of global climate change in this area, where is the most sensitive a... The detection of glacial lake change in the Himalayas, Nepal is extremely significant since the glacial lake change is one of the crucial indicators of global climate change in this area, where is the most sensitive area of the global climate changes. In the Hima- layas, some of glacial lakes are covered by the dark mountains' shadow because of their location. Therefore, these lakes can not be de- tected by conventional method such as Normalized Difference Water Index (NDWI), because the reflectance feature of shadowed glacial lake is different comparing to the ones which are located in the open flat area. The shadow causes two major problems: 1) glacial lakes which are covered by shadow completely result in underestimation of the number of glacial lakes; 2) glacial lakes which are partly iden- tified are considered to undervalue the area of glacial lakes. The aim of this study is to develop a new model, named Detection of Shadowed Glacial Lakes (DSGL) model, to identify glacial lakes under the shadow environment by using Advanced Space-borne Ther- mal Emission and Reflection Radiometer (ASTER) data in the Himalayas, Nepal. The DSGL model is based on integration of two dif- ferent modifications of NDWI, namely NDWls model and NDWIshe model. NDWI~ is defined as integration of the NDWI and slope analysis and used for detecting non-shadowed lake in the mountain area. The NDWIshe is proposed as a new methodology to overcome the weakness of NDWI~ on identifying shadowed lakes in highly elevated mountainous area such as the Himalayas. The first step of the NDWIshe is to enhance the data from ASTER 1B using the histogram equalization (HE) method, and its outcome product is named AS- TERho. We used the ASTERhe for calculating the NDWIhc and the NDWIshe. Integrated with terrain analysis using Digital Elevation Model (DEM) data, the NDWIshe can be used to identify the shadowed glacial lakes in the Himalayas. NDWIs value of 0.41 is used to identify the glacier lake (NDWI~ 〉 0.41), and 0.3 of NDWIshe is used to identify the shadowed glacier lake (NDWIsho 〈 0.3). The DSGL model was proved to be able to classify the glacial lakes more accurately, while the NDWI model had tendency to underestimate the presence of actual glacial lakes. Correct classification rate regarding the products from NDWI model and DSGL model were 57% and 99%, respectively. The results of this paper demonstrated that the DSGL model is promising to detect glacial lakes in the shadowed en- vironment at high mountains. 展开更多
关键词 glacial lake shadow environment DSGL model ASTER remote sensing HIMALAYAS Nepal
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Formation and water environmental evolution of the Nansihu Lake 被引量:1
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作者 ZHANGZulu SHENJi +2 位作者 LIUEnfeng SUNQingyi JIANGLuguang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期241-249,共9页
Through high-resolution research of sedimental chronology and the sediment environmental indexes, such as graininess, minerals, magnetic parameters, pigment content, organic carbon and chronology in Ds-co... Through high-resolution research of sedimental chronology and the sediment environmental indexes, such as graininess, minerals, magnetic parameters, pigment content, organic carbon and chronology in Ds-core and Ws-core in Nansihu Lake, the authors analyze the formation cause of the Nansihu Lake and its water environmental changes. Historical documents are also analyzed here in order to reach the conclusion. Researches indicate that the Nansihu Lake came into being about 2500 aBP and its evolution succession can be divided into four stages. In this evolution process, several scattered lakes merge into one large lake in the east of China. This process is distinctively affected by the overflow of the Yellow River, the excavation of the Grand Canal and other human activities. 展开更多
关键词 Nansihu lake lake sediment study water environment evolution migration and overflow of the Yellow River excavation of the Grand Canal CLC number:X144
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Response of Lake Environment to Climatic Changes on The Tibetan Plateau,Western China
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作者 LI Shijie JIANG Yongjian LUO Rongqin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期17-17,共1页
The large-scale summer monsoon circulations of south Asia makes a strong impact on precipitation in the area of southwestern China including Qinghai-Tibetan Plateau and Yun-Gui Plateau.however,the monsoon is both spat... The large-scale summer monsoon circulations of south Asia makes a strong impact on precipitation in the area of southwestern China including Qinghai-Tibetan Plateau and Yun-Gui Plateau.however,the monsoon is both spatially and temporally complex and smaller-scale circulations are forced by a variety of local or regional orographic effects,local or regional land-atmosphere or 展开更多
关键词 Climate changes lake environment Qinghai-Tibetan Plateau
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Characteristics of Water Environment in Regions of Zhaling and Eling Lakes near Waterhead of Yellow River
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作者 Cao Wenbing Wan Li Hu Fusheng Shen Zhaoli Department of Water Resources and Environmental Engineering, China University of Geosciences, Beijing 100083 Yan Weide Qinghai Exploring Institute of Hydrogeology and Engineering Geology, Ledu 810700 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期137-141,共5页
Conditions of the water environment in the region of the Zhaling and Eling lakes, which are located in the frozen earth zone on the Qingzang plateau, are unique. The equilibrium of the water quantity of the two lakes... Conditions of the water environment in the region of the Zhaling and Eling lakes, which are located in the frozen earth zone on the Qingzang plateau, are unique. The equilibrium of the water quantity of the two lakes is maladjustment under the condition of a dry and cold climate in which evaporation is greater than precipitation. The Zhaling and Eling lakes have been atrophying, leaving three lake terraces and star studded lagoons around the two lakes since Holocene. When these lagoons were separated from the original lakes, they became cut lake basins, and were transformed from fresh water lakes into salt water lakes, salt lakes or salt playas owing to strong evaporation. This kind of evolutionary process will continue in the future. 展开更多
关键词 water environment atrophy of lakes Zhaling and Eling lakes Qingzang plateau.
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The Effects of Pen Fish Culture on the Ecological Environments of Taihu Lake
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作者 YANGZai-fu CHENLi-qiao +5 位作者 LIUQi-gen SHIWei-gang CHENYong ZHOUZhong-liang SONGBin LIUHuan 《Agricultural Sciences in China》 CAS CSCD 2003年第12期1398-1403,共6页
Effects of pen fish culture in Taihu lake were studied and summarized. During 1984 to 2001, pen fish culture of Taihu lake developed from extensive models to intensive and high-returned ones, the cultured species were... Effects of pen fish culture in Taihu lake were studied and summarized. During 1984 to 2001, pen fish culture of Taihu lake developed from extensive models to intensive and high-returned ones, the cultured species were shifted from fishes to crabs. Pen fish culture has caused eutrophication and detrimental effect to the ecological environment and fishery. The measures of sustainable development for pen fish culture and ecological environment protection were suggested. 展开更多
关键词 Pen fish culture Taihu lake Ecological environment Measures of sustainable development
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A Fresh Look at the Geobiology & Sedimentary Environments of the Hypersaline Great Salt Lake,USA
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作者 Kathleen NICOLL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期94-95,共2页
1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recogni... 1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recognition of"bioherms,"algal layers,and mats covering hundreds of square km of lake area,these features have not been the 展开更多
关键词 lake Sedimentary environments of the Hypersaline Great Salt lake USA A Fresh Look at the Geobiology
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Ecological and environmental water demand of the lakes in the Haihe-Luanhe Basin of North China 被引量:18
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作者 LiuJL YongZF 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期234-238,共5页
The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe\|Luanhe Basin of Nor... The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe\|Luanhe Basin of North China was analyzed. The calculating method of the ecological and environmental water demand of the lake basis on the water body and the calculating method of the ecological and environmental water demand of the lake basis on the aquatic ecosystem, wetland and vegetation were compared and discussed. As the examples of Baiyangdian Lake and Beidagang Lake in Haihe\|Luanhe river basin, the ecological and environmental water demand of the two lakes was calculated to be 27×10\+8m\+3. It is 6.75 times to the water demand according to the calculating method of the ecological and environmental water demand of the lake basis on the water body. The research result indicated: (1) The calculating methods of the ecological and environmental water demand of the lake basis on the aquatic ecosystem should be better than only basis on the water body of lake. (2) The data, such as area of the vegetation kind around and in the lake, the vegetation coefficient, the evaporating amount of the vegetation and the vegetation water demand itself around and in the lake are lack and urgent need. Some suggestions for controlling and regulating the water resource of the lake in North China were proposed. 展开更多
关键词 eco\|environment water demand lake the Haihe\|Luanhe Basin
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Countermeasure and prospect of natural ecological environment in Qinghai lake
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《Global Geology》 1998年第1期49-50,共2页
关键词 Countermeasure and prospect of natural ecological environment in Qinghai lake
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Current Situation and Comprehensive Control Measures of Water Environment in the Chaohu Lake 被引量:1
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作者 Hu Mingming Ma Jianhua Zhu Xi 《Meteorological and Environmental Research》 CAS 2016年第6期45-50,共6页
Based on the analysis of current situation of water environment in the Chaohu Lake,general ideas and measures of controlling the water environment were proposed. In respect of control ideas,controlling outbreaks of bl... Based on the analysis of current situation of water environment in the Chaohu Lake,general ideas and measures of controlling the water environment were proposed. In respect of control ideas,controlling outbreaks of blue-green algae should be as one of control goals; it is needed to combine reducing the quantity of blue-green algae with decreasing eutrophication level to make the decrease in the quantity of blue-green algae larger than their natural increase until outbreaks of blue-green algae are eliminated; all kinds of techniques should be combined closely,integrated and innovated,and corresponding safeguard measures should be adopted. In respect of control measures,controlling sources of pollution and intercepting pollutants are basic measures,of which improving sewage treatment capacity and standard greatly is a key measure,and actively controlling pollution from large-scale livestock and poultry breeding is one of main measures; rivers polluted heavily should be controlled,and using microorganisms to purify small and moderate rivers can be as one of preferred techniques; blue-green algae should be dredged deeply to reducing their quantity; water should be transferred from the Yangtze River to the Chaohu Lake or the Hauihe River to purify water bodies and increase environmental capacity; reed wetland should be restored on a large scale to increase vegetation coverage from 5% to 20%; dredging should be combined with the elevation of basement of restored reed wetland. 展开更多
关键词 The CHAOHU lake Water environment Control measures CURRENT SITUATION China
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The structure of the plant communities in the different environment contact sites on the base of the soil-geobotanic profiling in the changing climate of Lake Baikal region 被引量:1
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作者 Alexander Sizykh Victor Voronin +1 位作者 Alexander Griczenuk Svetlana Sizykh 《Natural Science》 2012年第10期771-777,共7页
The results of studies of the peculiarities of formation of phytocenoses in environments contact sites of the western and eastern coasts of the Lake Baikal has been showed in this paper. On the base of geobotanic prof... The results of studies of the peculiarities of formation of phytocenoses in environments contact sites of the western and eastern coasts of the Lake Baikal has been showed in this paper. On the base of geobotanic profiling combined with soil one, the structure and dynamics of phytocenoses forming under the conditions of mutual development of light-coniferous taiga forest and of extra zonal steppes. Edaphic conditions and placement of phytocenoses are main trigger factors determining the ways of plant cover development in this part of Lake Baikal basin. We discuss the characteristics properties inherent in the linkage of the dynamics and spatial variability of the vegetation with the change of climate in the Baikal region. The regional conditions of the physiogeographic environment had given rise to structurally highly contrasting plant communities in this region. The increase in yearly mean summertime amounts of rainfall, combined with the rise of yearly mean winter temperatures over the last years were conducive to changes in the spatial structure of vegetation. The boundary between the types of vegetation undergoes smoothing. The upper boundary of forest is altered because of changes of the environment that are responsible for the zonality and properties of vertical zonality of the vegetation on the mountains surrounding Lake Baikal. Changes in the vegetation serve as indicators of climate change as well as providing diagnostic tools for the genesis of the Baikal region’s natural environment. 展开更多
关键词 Phytocenoses environments Contact Sites Soil-Geobotanic PROFILING Spatial Variability of Plant COMMUNITIES Taiga-Steppe COMMUNITIES lake BAIKAL REGION
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ABRUPT CHANGE OF LAKE ENVIRONMENT IN WEST CHINA: AN EVIDENCE FOR GLOBAL CLIMATE WARMING
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作者 Li Shijie, Shi Yafeng, Li Wanchun, Wu Jinglu, Yin Yu, Yang Xiangdong,Xia Weilan 《地学前缘》 EI CAS CSCD 2000年第S1期375-376,共2页
Expanding or shrinking of lakes, especially in the closed basin, directly reflects the balance situation of water\|heat regime in the catchment. Fluctuations of the water\|level can be used as an indicator of climatic... Expanding or shrinking of lakes, especially in the closed basin, directly reflects the balance situation of water\|heat regime in the catchment. Fluctuations of the water\|level can be used as an indicator of climatic and environmental changes. Authors have investigated many lakes in West China in recent years, including lakes in the Tibet Plateau and in the arid area in the northwest China. We found that all lakes have been in shrinkage, some of them were changed into swamp and some dried dramatically up, which caused the abrupt change of the lake environment. This change led the grassland to be retrogression and desertification, and made the eco\|environment deterioration in West China.The Xingcuo Lake, in the height of 3425m ASL with 29km\+2 drainage area, located in the Zoige Basin, Northeastern Tibet Plateau, had changed into swamp in the area of 2km\+2 , and the vast area of peripheral marsh changed into grassland by the years of 1990. But the topographic map in the scale of 1/100000 and aerial photography surveyed at the end of 1960’s show clearly that this lake was in the area of 3 3km\+2 and surrounded by vast area of marshland. In the north central part of the Tibet Plateau, the Gourencuo Lake, in the height of 4650m ASL, was in the area of 23 5km\+2 with the average water depth of 1 3m in 1990. Then a dramatic change had been appearing in the recent years. When authors went there again in 1998,they found that the lake dried fully up. A thin salt crystal layer with saturated brine covered the flat central lake floor. This means that at least 30×10 6 m 3 water volume stored in the lake had been lost by the evaporation in 8 years, and many sand dunes had been formed. This abrupt change of lake environment could be recognized as the result of natural process or climate warming because of no human activity there. 展开更多
关键词 ABRUPT change lake environment WEST China CLIMATE WARMING
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Multisource Disaster Chain and Control in Regional Water Environment of the Dongjiang Lake in China
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作者 Feng Gao Ronglan Xiao 《Journal of Water Resource and Protection》 2015年第15期1174-1182,共9页
On the background of analysis on region water environment safety in the Dongjiang Lake of south-central China, the source of pollution of water environment and its control are studied. The concept of region environmen... On the background of analysis on region water environment safety in the Dongjiang Lake of south-central China, the source of pollution of water environment and its control are studied. The concept of region environment disaster chain is put forward on the basis of combination study on the disaster chain theory and pollution problem in regional water environment. Through identification and analysis of pollution disaster resources in regional water environment of the Dongjiang Lake, the annual emission of the chemical oxygen demand (COD), ammonia nitrogen, total phosphorus (TP) and heavy metal (Cd, As, Pb) are counted. According to evaluation on structure proportion of contaminants in the Dongjiang Lake, agricultural non-point source is the uppermost pollution source, which accounted for 87.74% in total pollution load. Ammonia nitrogen, TP and COD are mainly contaminants accounted for 94.27% in total pollution load. By analyzing danger of contaminants in the lake, basic form of disaster chain of water environment pollution is built elementarily. It shows characteristics of branches and trunk basin disaster chain and embodies multisource disaster implication chain caused by human activities. Then, disaster resources chain-cutting methods for pollution prevention and control of regional water environment of the Dongjiang Lake are analyzed. 展开更多
关键词 Regional WATER environment DISASTER Chain Chain-Cutting DISASTER Mitigation from GESTATION Source WATER POLLUTION Control The Dongjiang lake
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Sea level change and environmental evolution of coastal lakes in Vestfold Hills, Antarctica
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作者 王自磐 《Chinese Journal of Polar Science》 2001年第1期9-20,共12页
Ecological and palaeoecological studies were carried out in a series of lakes in the Vestfold Hills (68°38′S, 78°06′E) on eastern Antarctic continent. Dynamics types of the lakes in environmental geomorpho... Ecological and palaeoecological studies were carried out in a series of lakes in the Vestfold Hills (68°38′S, 78°06′E) on eastern Antarctic continent. Dynamics types of the lakes in environmental geomorphology and physic chemistry, as well as features of biological community structures in different lakes were analyzed. Marine macro and micro fossils collected from the terraces and beaches surrounding these lakes and determined in 14 C radiocarbon ages to be the Late Pleistocene, were used as evidences to show the evolutionary processes of the lakes after sea level changes and transgressions since 18000 a B.P.. Basic modals of evolution for the lakes given in the paper could be regarded as not only explaining the history of environmental and ecological changes in VH lakes, and also reflecting of local environmental evolution in Antarctic region and global climate changes from past to present time. 展开更多
关键词 sea level change Antarctic continent environment of the lakes ecological evolution.
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Late Holocene Environmental History of Lake Victoria Basin: Evidence from Geochemical Proxies
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作者 Morgan Andama Julius B. Lejju +3 位作者 Casim Umba Tolo Grace Kagoro-Rugunda Immaculate Ssemmanda Janet Ayebare 《Journal of Environmental Science and Engineering(B)》 2012年第9期1054-1063,共10页
Sedimentary TOC (total organic carbon), TN (total nitrogen) and C/N (carbon/nitrogen) at selected sites of Lake Victoria basin have provided evidence of phytoplankton productivity, input of nitrates and allochth... Sedimentary TOC (total organic carbon), TN (total nitrogen) and C/N (carbon/nitrogen) at selected sites of Lake Victoria basin have provided evidence of phytoplankton productivity, input of nitrates and allochthonous (land) plant materials/catchment destruction in the basin during the late Holocene period (last 4,000 years to present). TOC and TN in the sediment cores were determined using EuroEA3000 Series Elemental Analyser and radiocarbon dating done using AMS (accelerator mass spectrometry) standard method. Results showed that TOC (13.45%-20.78%) and TN (1.07%-1.92%) values were higher at Napoleon Gulf from about 4,186 years before present (ca. 4,186 yr. BP) to present than at inlet of river Kagera (TOC: 3.27%-6.32% and TN: 0.30%-0.59%) from about 190 years before present (ca. 190 yr. BP) to present. Generally TOC and TN had a negative correlation (r = -0.37, p = 0.04, n = 32) at Napoleon Gulf in the last 4,186 years to present signifying that C/N ratios were governed mostly by phytoplankton productivity which markedly increased during some periods in the last 370 years to present possibly as a result of increased input of nitrates. However, the periods from about 4,186 years to 1,684 years before present (ca. 4,186 yr. BP to 1,684 yr. BP) and some periods between the last 370 years to present indicated increased input of allochthonous plant materials/catchment destruction. On overall, there was a positive correlation between C/N and TOC at inlet of river Kagera (r = 0.57, p = 0.01, n = 20) in the last 190 years to present possibly signifying that C/N ratios were governed mainly by input of allochthonous plant materials hence increased catchment destruction. Input of land plant materials (catchment destruction) along Kagera basin declined during some period after 1950 AD. However the most recent years have shown increased input of land plant materials (catchment destruction) in Kagera basin. 展开更多
关键词 environment geochemical proxies lake Victoria late Holocene.
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Catastrophic and persistent environmental consequences of an acid crater-lake discharge, Chiginagak Volcano, Alaska
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作者 Janet R. Schaefer William C. Evans +3 位作者 Bronwen Wang William E. Scott Robert G. McGimsey Janet Jorgenson 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期230-231,共2页
关键词 酸性 火山 深湖 地球化学
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